<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        * {
            margin: 0;
            padding: 0;
        }
        /* 基础样式 */
        .book {
            margin: 10px;
            padding: 15px;
            border: 1px solid #ccc;
        }
        [data-category="科幻"] {
            background-color: #007bff;
            color:white;
        }
        [data-category="历史"] {
            background-color: #8b4513;
            color: #fffdd0;
        }
        [title^="入门"] h2::before {
            content: "🌟";
            margin-right: 5px;
            font-size: 1.2em;
        }
    </style>
</head>
<body>
    <div class="book" data-category="科幻">
        <h2>三体</h2>
        <p>作者：刘慈欣</p>
    </div>
    <div class="book" data-category="历史">
        <h2>明朝那些事</h2>
        <p>作者：当年明月</p>
    </div>
    <div class="book" data-category="小说">
        <h2>活着</h2>
        <p>作者：余华</p>
    </div>
    <div class="book" data-category="语言学习" title="入门日语初级课程">
        <h2>日语初级课程</h2>
        <p>学习日常对话和基本语法</p>
    </div>
</body>
</html>